PLANET XRT-501 - Manual (Page 82)

Parameter Description
DoS Firewall
Enable DoS
Firewall
If enabled, DoS (Denial of Service) attacks will be detected and
blocked. The default is enabled. It is strongly recommended that
this setting be left enabled.
Note:
A DoS attack does not attempt to steal data or damage your
PCs, but overloads your Internet connection so you can not
use it - the service is unavailable.
This device uses "Stateful Inspection" technology. This
system can detect situations where individual TCP/IP packets
are valid, but collectively they become a DoS attack.
Firewall
Settings Button
If you wish to adjust the settings used by the DoS firewall, click
this button to open a sub-window.
Options
Respond to ICMP
The ICMP protocol is used by the "ping" and "traceroute"
programs, and by network monitoring and diagnostic programs.
If checked, the XRT-501 will repond to ICMP packets
received from the Internet.
If not checked, ICMP packets from the Internet will be
ignored. Disabling this option provides a slight increase in
security.
82